title: Anterior capsulotomy integrity after femtosecond laser-assisted cataract surgery.
abstract: OBJECTIVE
  To compare the incidence of anterior capsular tears after femtosecond laser-assisted cataract surgery (FLACS) versus phacoemulsification cataract surgery (PCS) and to assess the ultrastructural features of anterior capsulotomy specimens (FLACS and PCS) using electron microscopy.
  
  
  METHODS
  Prospective, multicenter, comparative cohort case series.
  
  
  METHODS
  Consecutive patients undergoing FLACS or PCS.
  
  
  METHODS
  A prospective cohort study of all patients (n = 1626) undergoing FLACS or PCS by 2 surgeons from centers A and B was undertaken to compare the incidence of anterior capsule tears. Anterior lens capsules were collected by 4 surgeons from centers A, B, C, and D using 3 different commercially available femtosecond platforms, each with latest version upgrades. Lens capsule tissue was prepared for scanning electron microscopy (SEM) using a total of 10 samples for patients undergoing PCS, and 40 samples for patients undergoing FLACS.
  
  
  METHODS
  Incidence of anterior capsule tear and comparative ultrastructural features of capsular samples from both PCS and FLACS cases.
  
  
  RESULTS
  There was a significantly increased rate of anterior capsule tears in the FLACS group (15/804 [1.87%]) when compared with the PCS group (1/822 [0.12%]; P = 0.0002, Fisher exact test). In 7 cases, the anterior capsule tear extended to the posterior capsule. Because all cases had occurred in complete capsulotomy, the integrity of the anterior capsule was questioned in the FLACS group. Subsequent SEM sampling showed irregularity at the capsule margin, as well as multiple apparently misplaced laser pits in normal parts of the tissue. Aberrant pits were approximately 2 to 4 μm apart and occurred at a range of 10 to 100 μm radially from the capsule edge.
  
  
  CONCLUSIONS
  Laser anterior capsulotomy integrity seems to be compromised by postage-stamp perforations and additional aberrant pulses, possibly because of fixational eye movements. This can lead to an increased rate of anterior capsule tears, and extra care should be taken during surgery after femtosecond laser pretreatment has been performed. A learning curve may account for some of the increased complication rate with FLACS. However, the SEM features raise safety concerns for capsular integrity after FLACS and warrant further investigation.
authors.affiliation: Tasmanian Eye Institute, Launceston, Tasmania, Australia.
authors.forename: Robin G
authors.initials: RG
authors.lastname: Abell
authors.affiliation: Newcastle Eye Hospital Research Foundation, Newcastle, New South Wales, Australia.
authors.forename: Peter E J
authors.initials: PEJ
authors.lastname: Davies
authors.affiliation: Electron Microscopy Unit, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Phelan
authors.affiliation: Central Sciences Laboratory, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Karsten
authors.initials: K
authors.lastname: Goemann
authors.affiliation: Newcastle Eye Hospital Research Foundation, Newcastle, New South Wales, Australia.
authors.forename: Zachary E
authors.initials: ZE
authors.lastname: McPherson
authors.affiliation: Tasmanian Eye Institute, Launceston, Tasmania, Australia. Electronic address: eye.vote@bigpond.net.au.
authors.forename: Brendan J
authors.initials: BJ
authors.lastname: Vote
mesh_terms: D000368:Aged; D057971:Anterior Capsular Rupture, Ocular / Q000209:etiology* / Q000473:pathology; D057866:Anterior Capsule of the Lens / Q000293:injuries* / Q000648:ultrastructure; D019923:Capsulorhexis; D002387:Cataract Extraction / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D053685:Laser Therapy / Q000009:adverse effects*; D059032:Learning Curve; D008297:Male; D008855:Microscopy, Electron, Scanning; D018918:Phacoemulsification / Q000009:adverse effects*; D011446:Prospective Studies